1
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Ky A, McCoy AJ, Flesher CG, Friend NE, Li J, Akinleye K, Patsalis C, Lumeng CN, Putnam AJ, O’Rourke RW. Matrix density regulates adipocyte phenotype. Adipocyte 2023; 12:2268261. [PMID: 37815174 PMCID: PMC10566443 DOI: 10.1080/21623945.2023.2268261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 09/29/2023] [Indexed: 10/11/2023] Open
Abstract
Alterations of the extracellular matrix contribute to adipose tissue dysfunction in metabolic disease. We studied the role of matrix density in regulating human adipocyte phenotype in a tunable hydrogel culture system. Lipid accumulation was maximal in intermediate hydrogel density of 5 weight %, relative to 3% and 10%. Adipogenesis and lipid and oxidative metabolic gene pathways were enriched in adipocytes in 5% relative to 3% hydrogels, while fibrotic gene pathways were enriched in 3% hydrogels. These data demonstrate that the intermediate density matrix promotes a more adipogenic, less fibrotic adipocyte phenotype geared towards increased lipid and aerobic metabolism. These observations contribute to a growing literature describing the role of matrix density in regulating adipose tissue function.
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Affiliation(s)
- Alexander Ky
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Atticus J. McCoy
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Carmen G. Flesher
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
- Graduate Program, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicole E. Friend
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Jie Li
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Kore Akinleye
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Christopher Patsalis
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
- Department of Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA
| | - Andrew J. Putnam
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Robert W. O’Rourke
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
- Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, USA
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2
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Strieder-Barboza, Flesher CG, Geletka LM, Eichler T, Akinleye O, Ky A, Ehlers AP, Lumeng CN, O’Rourke RW. Lumican modulates adipocyte function in obesity-associated type 2 diabetes. Adipocyte 2022; 11:665-675. [PMID: 36457256 PMCID: PMC9728465 DOI: 10.1080/21623945.2022.2154112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Obesity-associated type 2 diabetes (DM) leads to adipose tissue dysfunction. Lumican is a proteoglycan implicated in obesity, insulin resistance (IR), and adipocyte dysfunction. Using human visceral adipose tissue (VAT) from subjects with and without DM, we studied lumican effects on adipocyte function. Lumican was increased in VAT and adipocytes in DM. Lumican knockdown in adipocytes decreased lipolysis and improved adipogenesis and insulin sensitivity in VAT adipocytes in DM, while treatment with human recombinant lumican increased lipolysis and impaired insulin-sensitivity in an ERK-dependent manner. We demonstrate that lumican impairs adipocyte metabolism, partially via ERK signalling, and is a potential target for developing adipose tissue-targeted therapeutics in DM.
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Affiliation(s)
- Strieder-Barboza
- Department of Surgery , University of Michigan Medical School, MI, USA,Department of Veterinary Sciences, Texas Tech University, Lubbock , TX, USA,School of Veterinary Medicine, Texas Tech University, Amarillo, TX, USA
| | - Carmen G. Flesher
- Department of Surgery , University of Michigan Medical School, MI, USA
| | - Lynn M. Geletka
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
| | - Tad Eichler
- Department of Surgery , University of Michigan Medical School, MI, USA
| | - Olukemi Akinleye
- Department of Surgery , University of Michigan Medical School, MI, USA
| | - Alexander Ky
- Department of Surgery , University of Michigan Medical School, MI, USA
| | - Anne P. Ehlers
- Department of Surgery , University of Michigan Medical School, MI, USA,Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, USA
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA,Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI ,USA,Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert W. O’Rourke
- Department of Surgery , University of Michigan Medical School, MI, USA,Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, USA,CONTACT Robert W. O’Rourke Department of Surgery, Section of General Surgery, University of Michigan, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI48109-5343
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3
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Muir LA, Cho KW, Geletka LM, Baker NA, Flesher CG, Ehlers AP, Kaciroti N, Lindsly S, Ronquist S, Rajapakse I, O'Rourke RW, Lumeng CN. Human CD206+ macrophages associate with diabetes and adipose tissue lymphoid clusters. JCI Insight 2022; 7:146563. [PMID: 34990410 PMCID: PMC8855803 DOI: 10.1172/jci.insight.146563] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 12/15/2021] [Indexed: 12/03/2022] Open
Abstract
Increased adipose tissue macrophages (ATMs) correlate with metabolic dysfunction in humans and are causal in development of insulin resistance in mice. Recent bulk and single-cell transcriptomics studies reveal a wide spectrum of gene expression signatures possible for macrophages that depends on context, but the signatures of human ATM subtypes are not well defined in obesity and diabetes. We profiled 3 prominent ATM subtypes from human adipose tissue in obesity and determined their relationship to type 2 diabetes. Visceral adipose tissue (VAT) and s.c. adipose tissue (SAT) samples were collected from diabetic and nondiabetic obese participants to evaluate cellular content and gene expression. VAT CD206+CD11c- ATMs were increased in diabetic participants, were scavenger receptor-rich with low intracellular lipids, secreted proinflammatory cytokines, and diverged significantly from 2 CD11c+ ATM subtypes, which were lipid-laden, were lipid antigen presenting, and overlapped with monocyte signatures. Furthermore, diabetic VAT was enriched for CD206+CD11c- ATM and inflammatory signatures, scavenger receptors, and MHC II antigen presentation genes. VAT immunostaining found CD206+CD11c- ATMs concentrated in vascularized lymphoid clusters adjacent to CD206-CD11c+ ATMs, while CD206+CD11c+ were distributed between adipocytes. Our results show ATM subtype-specific profiles that uniquely contribute to the phenotypic variation in obesity.
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Affiliation(s)
| | | | | | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Carmen G Flesher
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Anne P Ehlers
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Department of Surgery, Ann Arbor Veterans Affairs Healthcare System, Ann Arbor, Michigan, USA
| | - Niko Kaciroti
- Center for Human Growth and Development, University of Michigan, Ann Arbor, Michigan, USA.,Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, Michigan, USA
| | - Stephen Lindsly
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Scott Ronquist
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Indika Rajapakse
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Department of Mathematics and.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan, USA.,Department of Surgery, Ann Arbor Veterans Affairs Healthcare System, Ann Arbor, Michigan, USA
| | - Carey N Lumeng
- Department of Pediatrics and.,Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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4
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Carruthers NJ, Strieder-Barboza C, Caruso JA, Flesher CG, Baker NA, Kerk SA, Ky A, Ehlers AP, Varban OA, Lyssiotis CA, Lumeng CN, Stemmer PM, O'Rourke RW. The human type 2 diabetes-specific visceral adipose tissue proteome and transcriptome in obesity. Sci Rep 2021; 11:17394. [PMID: 34462518 PMCID: PMC8405693 DOI: 10.1038/s41598-021-96995-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 08/11/2021] [Indexed: 01/21/2023] Open
Abstract
Dysfunctional visceral adipose tissue (VAT) in obesity is associated with type 2 diabetes (DM) but underlying mechanisms remain unclear. Our objective in this discovery analysis was to identify genes and proteins regulated by DM to elucidate aberrant cellular metabolic and signaling mediators. We performed label-free proteomics and RNA-sequencing analysis of VAT from female bariatric surgery subjects with DM and without DM (NDM). We quantified 1965 protein groups, 23 proteins, and 372 genes that were differently abundant in DM vs. NDM VAT. Proteins downregulated in DM were related to fatty acid synthesis and mitochondrial function (fatty acid synthase, FASN; dihydrolipoyl dehydrogenase, mitochondrial, E3 component, DLD; succinate dehydrogenase-α, SDHA) while proteins upregulated in DM were associated with innate immunity and transcriptional regulation (vitronectin, VTN; endothelial protein C receptor, EPCR; signal transducer and activator of transcription 5B, STAT5B). Transcriptome indicated defects in innate inflammation, lipid metabolism, and extracellular matrix (ECM) function, and components of complement classical and alternative cascades. The VAT proteome and transcriptome shared 13 biological processes impacted by DM, related to complement activation, cell proliferation and migration, ECM organization, lipid metabolism, and gluconeogenesis. Our data revealed a marked effect of DM in downregulating FASN. We also demonstrate enrichment of complement factor B (CFB), coagulation factor XIII A chain (F13A1), thrombospondin 1 (THBS1), and integrins at mRNA and protein levels, albeit with lower q-values and lack of Western blot or PCR confirmation. Our findings suggest putative mechanisms of VAT dysfunction in DM.
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Affiliation(s)
- Nicholas J Carruthers
- Proteomics Core Facility, Wayne State University, 42 W. Warren Ave, Detroit, MI, 48202, USA
| | - Clarissa Strieder-Barboza
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Joseph A Caruso
- Department of Chemistry, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Carmen G Flesher
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Samuel A Kerk
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Division of Gastroenterology, Department of Internal Medicine, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Rogel Cancer Center, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Alexander Ky
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Anne P Ehlers
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, 2215 Fuller Rd, Ann Arbor, MI, 48105, USA
| | - Oliver A Varban
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Costas A Lyssiotis
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Division of Gastroenterology, Department of Internal Medicine, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Rogel Cancer Center, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Graduate Program in Immunology, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA.,Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA
| | - Paul M Stemmer
- Proteomics Core Facility, Wayne State University, 42 W. Warren Ave, Detroit, MI, 48202, USA
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School, 1301 Catherine St, Ann Arbor, MI, 48109, USA. .,Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, 2215 Fuller Rd, Ann Arbor, MI, 48105, USA. .,Section of General Surgery, Department of Surgery, University of Michigan, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA.
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5
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Juliar BA, Strieder-Barboza C, Karmakar M, Flesher CG, Baker NA, Varban OA, Lumeng CN, Putnam AJ, O'Rourke RW. Viscoelastic characterization of diabetic and non-diabetic human adipose tissue. Biorheology 2021; 57:15-26. [PMID: 32083565 DOI: 10.3233/bir-190234] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Obesity-induced chronic inflammation and fibrosis in adipose tissue contributes to the progression of type 2 diabetes mellitus (DM). While fibrosis is known to induce mechanical stiffening of numerous tissue types, it is unknown whether DM is associated with alterations in adipose tissue mechanical properties. OBJECTIVE The purpose of this study was to investigate whether DM is associated with differences in bulk viscoelastic properties of adipose tissue from diabetic (DM) and non-diabetic (NDM) obese subjects. METHODS Bulk shear rheology was performed on visceral (VAT) and subcutaneous (SAT) adipose tissue, collected from obese subjects undergoing elective bariatric surgery. Rheology was also performed on the remaining extracellular matrix (ECM) from decellularized VAT (VAT ECM). Linear mixed models were used to assess whether correlations existed between adipose tissue mechanical properties and DM status, sex, age, and body mass index (BMI). RESULTS DM was not associated with significant differences in adipose tissue viscoelastic properties for any of the tissue types investigated. Tissue type dependent differences were however detected, with VAT having significantly lower shear storage and loss moduli than SAT and VAT ECM independent of DM status. CONCLUSION Although DM is typically associated with adipose tissue fibrosis, it is not associated with differences in macroscopic adipose tissue mechanical properties.
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Affiliation(s)
- Benjamin A Juliar
- Department of Biomedical Engineering, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Clarissa Strieder-Barboza
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, \unskip\break Ann Arbor, MI, USA
| | - Monita Karmakar
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carmen G Flesher
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Oliver A Varban
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, \unskip\break Ann Arbor, MI, USA.,Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA.,Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, \unskip\break Ann Arbor, MI, USA
| | - Andrew J Putnam
- Department of Biomedical Engineering, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA.,Department of Surgery, Ann Arbor Veterans Affairs Healthcare System, Ann Arbor, MI, USA
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6
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Youngblood R, Flesher CG, Delproposto J, Baker NA, Neeley CK, Li F, Lumeng CN, Shea LD, O'Rourke RW. Regulation of adipose tissue inflammation and systemic metabolism in murine obesity by polymer implants loaded with lentiviral vectors encoding human interleukin-4. Biotechnol Bioeng 2020; 117:3891-3901. [PMID: 32729936 PMCID: PMC8358590 DOI: 10.1002/bit.27523] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 07/26/2020] [Accepted: 07/28/2020] [Indexed: 11/08/2022]
Abstract
Dysfunctional adipose tissue plays a central role in the pathogenesis of the obesity-related metabolic disease, including type 2 diabetes. Targeting adipose tissue using biopolymer implants is a novel therapeutic approach for metabolic disease. We transplanted porous poly(lactide-co-glycolide) (PLG) implants coated with human interleukin-4 (hIL-4)-expressing lentivirus into epididymal white adipose tissue (eWAT) of mice fed a high-fat diet. Tissue and systemic inflammation and metabolism were studied with flow cytometry, immunohistochemistry, quantitative real-time polymerase chain reaction, adipose tissue histology, and in vivo glucose tolerance testing at 2 and 10 weeks of a high-fat diet. PLG implants carrying hIL-4-expressing lentivirus implanted into epididymal white adipose tissue of mice-regulated adipose tissue inflammation, including increased CD3+ CD4+ T-cell frequency, increased eWAT adipocyte hypertrophy, and decreased FASN and ATGL expression, along with reduced fasting blood glucose levels. These effects were observed in early obesity but were not maintained in established obesity. Local delivery of bioimplants loaded with cytokine-expressing lentivirus vectors to adipose tissue influences tissue inflammation and systemic metabolism in early obesity. Further study will be required to show more durable metabolic effects. These data demonstrate that polymer biomaterials implanted into adipose tissue have the potential to modulate local tissue and systemic inflammation and metabolism.
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Affiliation(s)
- Richard Youngblood
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Carmen G Flesher
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Jennifer Delproposto
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
| | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Christopher K Neeley
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
| | - Fanghua Li
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
- Graduate Program in Immunology, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan
- Graduate Program in Cellular and Molecular Biology, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan
| | - Lonnie D Shea
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan
- Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan
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7
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Abstract
Subcutaneous (SAT) and visceral (VAT) adipose tissues have distinct metabolic phenotypes. We hypothesized that the extracellular matrix (ECM) regulates depot-specific differences in adipocyte metabolic function in murine obesity. VAT and SAT preadipocytes from lean or obese mice were subject to adipogenic differentiation in standard 2D culture on plastic tissue culture plates or in 3D culture in ECM, followed by metabolic profiling. Adipocytes from VAT relative to SAT manifested impaired insulin-stimulated glucose uptake and decreased adipogenic capacity. In 3D-ECM-adipocyte culture, ECM regulated adipocyte metabolism in a depot-specific manner, with SAT ECM rescuing defects in glucose uptake and adipogenic gene expression in VAT adipocytes, while VAT ECM impaired adipogenic gene expression in SAT adipocytes. These findings demonstrate that ECM-adipocyte crosstalk regulates depot-specific differences in adipocyte metabolic dysfunction in murine obesity.
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Affiliation(s)
- Clarissa Strieder-Barboza
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Nicki A. Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carmen G. Flesher
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Monita Karmakar
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ayush Patel
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, MI, USA
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, USA
| | - Robert W. O’Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, USA
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8
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Wenderott JK, Flesher CG, Baker NA, Neeley CK, Varban OA, Lumeng CN, Muhammad LN, Yeh C, Green PF, O'Rourke RW. Elucidating nanoscale mechanical properties of diabetic human adipose tissue using atomic force microscopy. Sci Rep 2020; 10:20423. [PMID: 33235234 PMCID: PMC7686328 DOI: 10.1038/s41598-020-77498-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 11/11/2020] [Indexed: 01/07/2023] Open
Abstract
Obesity-related type 2 diabetes (DM) is a major public health concern. Adipose tissue metabolic dysfunction, including fibrosis, plays a central role in DM pathogenesis. Obesity is associated with changes in adipose tissue extracellular matrix (ECM), but the impact of these changes on adipose tissue mechanics and their role in metabolic disease is poorly defined. This study utilized atomic force microscopy (AFM) to quantify difference in elasticity between human DM and non-diabetic (NDM) visceral adipose tissue. The mean elastic modulus of DM adipose tissue was twice that of NDM adipose tissue (11.50 kPa vs. 4.48 kPa) to a 95% confidence level, with significant variability in elasticity of DM compared to NDM adipose tissue. Histologic and chemical measures of fibrosis revealed increased hydroxyproline content in DM adipose tissue, but no difference in Sirius Red staining between DM and NDM tissues. These findings support the hypothesis that fibrosis, evidenced by increased elastic modulus, is enhanced in DM adipose tissue, and suggest that measures of tissue mechanics may better resolve disease-specific differences in adipose tissue fibrosis compared with histologic measures. These data demonstrate the power of AFM nanoindentation to probe tissue mechanics, and delineate the impact of metabolic disease on the mechanical properties of adipose tissue.
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Affiliation(s)
- J K Wenderott
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60201, USA
| | - Carmen G Flesher
- Department of Surgery, Section of General Surgery, University of Michigan Medical School, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA
| | - Nicki A Baker
- Department of Surgery, Section of General Surgery, University of Michigan Medical School, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA
| | - Christopher K Neeley
- Department of Surgery, Section of General Surgery, University of Michigan Medical School, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA
| | - Oliver A Varban
- Department of Surgery, Section of General Surgery, University of Michigan Medical School, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA
| | - Carey N Lumeng
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI, 48109, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - Lutfiyya N Muhammad
- Division of Biostatistics, Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, USA
| | - Chen Yeh
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60201, USA
| | - Peter F Green
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109, USA.
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, 48109, USA.
- National Renewable Energy Laboratory, Golden, CO, 80401, USA.
| | - Robert W O'Rourke
- Department of Surgery, Section of General Surgery, University of Michigan Medical School, 2210 Taubman Center-5343, 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5343, USA.
- Department of Surgery, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, MI, 48109, USA.
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9
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Flesher CG, Baker NA, Strieder-Barboza C, Polsinelli D, Webster PJ, Varban OA, Lumeng CN, O'Rourke RW. A Human 3D Extracellular Matrix-Adipocyte Culture Model for Studying Matrix-Cell Metabolic Crosstalk. J Vis Exp 2019. [PMID: 31762470 DOI: 10.3791/60486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The extracellular matrix (ECM) plays a central role in regulating tissue homeostasis, engaging in crosstalk with cells and regulating multiple aspects of cellular function. The ECM plays a particularly important role in adipose tissue function in obesity, and alterations in adipose tissue ECM deposition and composition are associated with metabolic disease in mice and humans. Tractable in vitro models that permit dissection of the roles of the ECM and cells in contributing to global tissue phenotype are sparse. We describe a novel 3D in vitro model of human ECM-adipocyte culture that permits study of the specific roles of the ECM and adipocytes in regulating adipose tissue metabolic phenotype. Human adipose tissue is decellularized to isolate ECM, which is subsequently repopulated with preadipocytes that are then differentiated within the ECM into mature adipocytes. This method creates ECM-adipocyte constructs that are metabolically active and retain characteristics of the tissues and patients from which they are derived. We have used this system to demonstrate disease-specific ECM-adipocyte crosstalk in human adipose tissue. This culture model provides a tool for dissecting the roles of the ECM and adipocytes in contributing to global adipose tissue metabolic phenotype and permits study of the role of the ECM in regulating adipose tissue homeostasis.
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Affiliation(s)
| | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School
| | - Clarissa Strieder-Barboza
- Department of Surgery, University of Michigan Medical School; Department of Pediatrics and Communicable Diseases, University of Michigan Medical School
| | | | - Phillip J Webster
- Department of Surgery, University of Michigan Medical School; Department of Pediatrics and Communicable Diseases, University of Michigan Medical School
| | - Oliver A Varban
- Department of Surgery, University of Michigan Medical School
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School; Graduate Program in Immunology, University of Michigan Medical School; Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School; Department of Surgery, Ann Arbor Veterans Affairs Healthcare System;
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10
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Muir LA, Baker NA, Washabaugh AR, Neeley CK, Flesher CG, DelProposto JB, Geletka LM, Ghaferi AA, Finks JF, Singer K, Varban OA, Lumeng CN, O'Rourke RW. Adipocyte hypertrophy-hyperplasia balance contributes to weight loss after bariatric surgery. Adipocyte 2017; 6:134-140. [PMID: 28425841 DOI: 10.1080/21623945.2017.1287639] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Predictors of weight loss responses are not well-defined. We hypothesized that adipose tissue phenotypic features related to remodeling would be associated with bariatric surgery weight loss responses. Visceral and subcutaneous adipose tissues collected from patients during bariatric surgery were studied with flow cytometry, immunohistochemistry, and QRTPCR, and results correlated with weight loss outcomes. Age, male sex, and a diagnosis of type 2 diabetes were associated with less weight loss. Adipocyte size was increased and preadipocyte frequency was decreased in visceral adipose tissue from diabetic subjects. Decreased adipose tissue preadipocyte frequency was associated with less weight loss in women but not men. These data suggest that phenotypic features of adipose tissue remodeling may predict responses to weight loss interventions.
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Affiliation(s)
- Lindsey A. Muir
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Nicki A. Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Alexandra R. Washabaugh
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Christopher K. Neeley
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carmen G. Flesher
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jennifer B. DelProposto
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lynn M. Geletka
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Amir A. Ghaferi
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, Ann Arbor Veteran's Administration Hospital, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jonathan F. Finks
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Kanakadurga Singer
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Oliver A. Varban
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert W. O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, Ann Arbor Veteran's Administration Hospital, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
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11
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Baker NA, Muir LA, Washabaugh AR, Neeley CK, Chen SYP, Flesher CG, Vorwald J, Finks JF, Ghaferi AA, Mulholland MW, Varban OA, Lumeng CN, O’Rourke RW. Diabetes-Specific Regulation of Adipocyte Metabolism by the Adipose Tissue Extracellular Matrix. J Clin Endocrinol Metab 2017; 102:1032-1043. [PMID: 28359093 PMCID: PMC5460687 DOI: 10.1210/jc.2016-2915] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 12/30/2016] [Indexed: 01/15/2023]
Abstract
CONTEXT The role of the extracellular matrix (ECM) in regulating adipocyte metabolism in the context of metabolic disease is poorly defined. OBJECTIVE The objective of this study was to define the metabolic phenotype of adipocytes associated with human diabetes (DM) and the role of the ECM in regulating adipocyte metabolism. DESIGN Adipose tissues from obese patients were studied in standard 2-dimensional (2D) cell culture and an in vitro model of decellularized adipose tissue ECM repopulated with human adipocytes, and results were correlated with DM status. SETTING This study was conducted at the Academic University Medical Center and Veteran's Administration Hospital. PATIENTS Seventy patients with morbid obesity undergoing bariatric surgery were included in the study. INTERVENTIONS Visceral and subcutaneous adipose tissues were collected at the time of bariatric surgery. OUTCOME MEASURES This study used metabolic assays for glucose uptake, lipolysis, and lipogenesis in adipocytes in 2D cell culture and 3-dimensional ECM culture. RESULTS Adipocytes from subjects with DM manifest decreased glucose uptake and decreased lipolysis in 2D culture. ECM supports differentiation of mature adipocytes and recapitulates DM-specific differences in adipocyte metabolism observed in 2D culture. ECM from subjects without DM partially rescues glucose uptake and lipolytic defects in adipocytes from subjects with DM, whereas ECM from subjects with DM impairs glucose uptake in adipocytes from subjects without DM. CONCLUSIONS DM is associated with adipocyte metabolic dysfunction. The ECM regulates adipocyte metabolism. Nondiabetic ECM rescues metabolic dysfunction in DM adipocytes, whereas DM ECM imparts features of metabolic dysfunction to nondiabetic adipocytes. These findings suggest the ECM as a target for manipulating adipose tissue metabolism.
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Affiliation(s)
| | | | | | | | | | - Carmen G. Flesher
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, Michigan 48109; and
| | - John Vorwald
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, Michigan 48109; and
| | | | - Amir A. Ghaferi
- Department of Surgery,
- Department of Surgery, Ann Arbor Veteran’s Administration Hospital, Ann Arbor, Michigan 48109
| | | | | | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases,
- Graduate Program in Immunology, and
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, Michigan 48109;
| | - Robert W. O’Rourke
- Department of Surgery,
- Department of Surgery, Ann Arbor Veteran’s Administration Hospital, Ann Arbor, Michigan 48109
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12
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Meyer KA, Neeley CK, Baker NA, Washabaugh AR, Flesher CG, Nelson BS, Frankel TL, Lumeng CN, Lyssiotis CA, Wynn ML, Rhim AD, O'Rourke RW. Adipocytes promote pancreatic cancer cell proliferation via glutamine transfer. Biochem Biophys Rep 2016; 7:144-149. [PMID: 27617308 PMCID: PMC5014359 DOI: 10.1016/j.bbrep.2016.06.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Adipocytes promote progression of multiple cancers, but their role in pancreatic intraepithelial neoplasia (PanIN) and ductal adenocarcinoma (PDAC) is poorly defined. Nutrient transfer is a mechanism underlying stromal cell-cancer crosstalk. We studied the role of adipocytes in regulating in vitro PanIN and PDAC cell proliferation with a focus on glutamine metabolism. Murine 3T3L1 adipocytes were used to model adipocytes. Cell lines derived from PKCY mice were used to model PanIN and PDAC. Co-culture was used to study the effect of adipocytes on PanIN and PDAC cell proliferation in response to manipulation of glutamine metabolism. Glutamine secretion was measured with a bioanalyzer. Western blotting was used to study the effect of PanIN and PDAC cells on expression of glutamine-related enzymes in adipocytes. Adipocytes promote proliferation of PanIN and PDAC cells, an effect that was amplified in nutrient-poor conditions. Adipocytes secrete glutamine and rescue PanIN and PDAC cell proliferation in the absence of glutamine, an effect that was glutamine synthetase-dependent and involved PDAC cell-induced down-regulation of glutaminase expression in adipocytes. These findings suggest glutamine transfer as a potential mechanism underlying adipocyte-induced PanIN and PDAC cell proliferation.
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Affiliation(s)
- Kevin A Meyer
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Christopher K Neeley
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Nicki A Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Carmen G Flesher
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, MI, USA
| | - Barbara S Nelson
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Timothy L Frankel
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Surgery, Ann Arbor Veteran's Administration Hospital, Ann Arbor, MI, USA
| | - Carey N Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Costas A Lyssiotis
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Michelle L Wynn
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA; Division of Hematology and Oncology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Andrew D Rhim
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert W O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Surgery, Ann Arbor Veteran's Administration Hospital, Ann Arbor, MI, USA
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13
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Muir LA, Neeley CK, Meyer KA, Baker NA, Brosius AM, Washabaugh AR, Varban OA, Finks JF, Zamarron BF, Flesher CG, Chang JS, DelProposto JB, Geletka L, Martinez-Santibanez G, Kaciroti N, Lumeng CN, O'Rourke RW. Adipose tissue fibrosis, hypertrophy, and hyperplasia: Correlations with diabetes in human obesity. Obesity (Silver Spring) 2016; 24:597-605. [PMID: 26916240 PMCID: PMC4920141 DOI: 10.1002/oby.21377] [Citation(s) in RCA: 217] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Revised: 09/19/2015] [Accepted: 09/26/2015] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The relationship between adipose tissue fibrosis, adipocyte hypertrophy, and preadipocyte hyperplasia in the context of obesity and the correlation of these tissue-based phenomena with systemic metabolic disease are poorly defined. The goal of this study was to clarify the relationship between adipose tissue fibrosis, adipocyte hypertrophy, and preadipocyte hyperplasia in human obesity and determine the correlation of these adipose-tissue based phenomena with diabetes. METHODS Visceral and subcutaneous adipose tissues from humans with obesity collected during bariatric surgery were studied with QRTPCR, immunohistochemistry, and flow cytometry for expression of collagens and fibrosis-related proteins, adipocyte size, and preadipocyte frequency. Results were correlated with clinical characteristics including diabetes status. RESULTS Fibrosis was decreased, hypertrophy was increased, and preadipocyte frequency and fibrotic gene expression were decreased in adipose tissues from diabetic subjects compared to non-diabetic subjects. These differences were greater in visceral compared to subcutaneous adipose tissue. CONCLUSIONS These data are consistent with the hypothesis that adipose tissue fibrosis in the context of human obesity limits adipocyte hypertrophy and is associated with a reciprocal increase in adipocyte hyperplasia, with beneficial effects on systemic metabolism. These findings suggest adipose tissue fibrosis as a potential target for manipulation of adipocyte metabolism.
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Affiliation(s)
- Lindsey A. Muir
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Kevin A. Meyer
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Nicki A. Baker
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Alice M. Brosius
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Oliver A. Varban
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jonathan F. Finks
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Brian F. Zamarron
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carmen G. Flesher
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, MI, USA
| | - Joshua S. Chang
- Undergraduate Research Opportunity Program, University of Michigan, Ann Arbor, MI, USA
| | - Jennifer B. DelProposto
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Lynn Geletka
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Gabriel Martinez-Santibanez
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Niko Kaciroti
- Center for Human Growth and Development, University of Michigan, Ann Arbor, MI, USA
- Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Carey N. Lumeng
- Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Robert W. O'Rourke
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
- Department of Surgery, Ann Arbor Veteran's Administration Hospital, Ann Arbor, MI, USA
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